Test apparatus and method for nondestructive material testing

Abstract

The test apparatus for nondestructive material testing using electrodynamically generated ultrasonic waves. A high-frequency coil assembly has an end face perpendicular to a surface of the workpiece and it is disposed between at least two magnets. Efficient generation and reception of ultrasonic waves is thereby assured.

We claim: 
     
       1. A test apparatus for nondestructive testing of a workpiece, comprising: at least two mutually spaced-apart magnets with a gap therebetween; and   a high-frequency coil assembly electrodynamically generating ultrasonic waves, said high-frequency coil assembly being disposed in the gap between said magnets and having an end face extending perpendicularly to a surface of the workpiece.   
     
     
       2. The test apparatus according to claim 1, wherein said magnets and said high-frequency coil assembly each have coupling faces, said coupling faces of said magnets and of said high-frequency coil assembly being disposed substantially in a common plane, and wherein said magnets are oriented perpendicular to the surface of the workpiece. 
     
     
       3. The test apparatus according to claim 1, wherein said high-frequency coil assembly has a longitudinal axis and a coil core disposed along said longitudinal axis. 
     
     
       4. The test apparatus according to claim 3, wherein said coil core is formed of soft magnetic material. 
     
     
       5. The test apparatus according to claim 3, wherein said coil core is a cylinder. 
     
     
       6. The test apparatus according to claim 5, wherein said coil core is formed of soft magnetic material. 
     
     
       7. The test apparatus according to claim 3, wherein said coil core is a parallelepiped. 
     
     
       8. The test apparatus according to claim 7, wherein said coil core is formed of soft magnetic material. 
     
     
       9. The test apparatus according to claim 3, wherein said high-frequency coil assembly has a winding wound tightly on said coil core. 
     
     
       10. The test apparatus according to claim 1, wherein said high-frequency coil assembly is formed with end faces and said magnets are disposed on said end faces of said high-frequency coil assembly. 
     
     
       11. The test apparatus according to claim 1, wherein said high-frequency coil assembly is formed with end faces, and said magnets are parallel to said end faces and aligned one behind the other in alternating magnetic orientation. 
     
     
       12. The test apparatus according to claim 1, wherein said magnets are permanent magnets. 
     
     
       13. The test apparatus according to claim 1, wherein said magnets are electromagnets. 
     
     
       14. A method of nondestructive testing of a workpiece with a surface, which comprises: placing a high-frequency coil assembly in a gap between at least two mutually spaced-apart magnets, and coupling the high-frequency coil assembly to a workpiece, with an end face of the coil assembly extending perpendicularly to a surface of the workpiece; and   electrodynamically generating ultrasonic waves with the high-frequency coil assembly.